When you play media or get notifications, does it come out the main speaker ok, or is that also silent? If it's silent, then make sure the headphone jack is also clear of debris. Use a can of compressed air to blow it out, and a toothpick to root around. Sometimes, a chunk of something lodged in the jack can make the phone think that a headphone is always plugged in (or it could be that the jack is the faulty part, not the speakers).